Since moving to nova-cells a few months back, we really wanted to still utilize host aggregates and availability zones.

Fortunately, we were able to piggyback off work NeCTAR had done to implement this functionality.  Here’s a list of patches we pulled in, and they’ve been working well.

• nova-api server read cell state from DB:  https://github.com/NeCTAR-RC/nova/commit/6fe7057fb4957485d3bac06579ddc38c93458064
• Add AZ support for cells:  https://github.com/NeCTAR-RC/nova/commit/048bd2d6d438fb8fa9ad7d3e0d57e7d03c546f6f
• Support aggregate API in cells:  https://github.com/NeCTAR-RC/nova/commit/8ca8828d191bc271460eb80567717fd15ef6167c
• Ability to filter cells capacity report:  https://github.com/NeCTAR-RC/nova/commit/97921ef1010c5e5bca357d77682bd0ee42d6ffcc 
• Print cell name in cell timeout exceptions:  https://github.com/NeCTAR-RC/nova/commit/60f669ba1ed5221d71138a72fb2cf3b34c07a970 
• Use sysmetadata to get instances AZ in API cell:  https://github.com/NeCTAR-RC/nova/commit/95e4cccac623c601e074a618ea71d121a359e00f 
• Use sysmetadata to get instance_name in API cell:  https://github.com/NeCTAR-RC/nova/commit/6bf1cf78b86bed99733e1119b891397dee15a65e 
• Cells support for flavors:  https://github.com/NeCTAR-RC/nova/commit/5abc8847dc89b162b6ae678176a5cfe4989144a9

A big thanks to the NeCTAR team, especially Sam Morrison, for all the help with this!